Ukraine has systematically removed Russian capabilities around Crimea: 

-Destroyed S-400 launcher at Cape Tarkhankut
-Removed radar and sensors from oil/gas platforms in Black Sea 
-Facilitating attacks on Russian Black Sea Fleet ships in Sevastopol 
-Hit S-400 at Yevpatoria

attempting to take out Russian AD capabilities around peninsula in order to be able to conduct more deep strikes using SBU drones and Air Force Storm Shadow air-launched cruise missiles and Navy Neptune anti-ship missiles.

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